The design of our barn, when completed, allows for two levels, the upper one containing hay storage and drying racks. Once that is all done (some time next year), there will be a ceiling to the animal pens below, closing them off from the feeding alley and grain storage area.
However, in the meantime, that ceiling was open and guineas can fly really well, meaning that they were getting into all kinds of shit: rabbit feeders, barrels of food, the shelving unit that contains first aid, tools, plumbing parts, etc. Every morning, they were causing some new kind of trouble.
We did this a few weeks ago and the result has been fantastic. The guineas can no longer get into “our” part of the barn.
Now we just have to deal with keeping the guineas off the barn roof and the chickens out of the garden!